Protecting Biospheres Beyond Earth
SpaceDaily

A new era in space exploration is slowly opening up as we prepare for the return of samples beyond the Moon: from comets, Mars and Europa. But there is a downside to this glorious new age of exploration – two downsides, actually. Firstly there is a good deal of apprehension among the general public that samples returned from other worlds such as Mars – just might – contain alien germs capable of turning into a worldwide plague, or at least wreaking havoc with the Earth’s natural environment. Beside this fear of “back contamination”, there is also a fear of “forward contamination” – the possibility that spacecraft might contaminate the worlds they land on with Earth microbes, destroying scientifically priceless alien lifeforms before we even have a chance to study them.